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El presente proyecto se basa en la producción y comercialización de ropa interior para las mujeres de edades entre los 19 y 49 años del nivel socioeconómico A y B de Lima metropolitana, especialmente para aquellas que presentan flujo abundante. Se realizaron encuestas que permitieron detectar una demanda insatisfecha debido a la falta de productos que brinden seguridad y comodidad al momento de usar una prenda interior en el periodo menstrual. Cuenta con un diseño especial en la zona del fundillo, el cual está compuesto por 3 tipos de tela, algodón licra, tela de bambú y algodón jersey, los mismos que permite reducir el riesgo de manchar las prendas de vestir cuando realizan actividades cotidianas. La medida es de 24 cm de largo, lo cual abarca gran parte de zona delantera y trasera de la trusa. El desarrollo del proyecto se encuentra dividido en dos puntos, los cuales son la validación del plan de negocio y desarrollo del plan de negocio. Para la ejecución del proyecto se requirió una inversión de 23,888 soles, obtenidos a base de capital propio de los accionistas, quienes estiman recuperar dicha inversión en el primer año de operación. La rentabilidad brindada a los accionistas es de 274% lo cual hace nuestro proyecto un negocio rentable. / The present project is based on the production and marketing of underwear for women between the ages of 19 and 49, with socioeconomic statuses A and B in metropolitan Lima, especially for those who have an abundant flow. Surveys were conducted that allowed us to detect an unmet demand due to the lack of products that provide safety and comfort when wearing an undergarment during the menstrual period. It has a special design in the delicate area of the underwear, which is composed of 3 types of cloths, lycra cotton, bamboo cloth and cotton jersey, the same that reduces the risk of staining garments when the users perform their daily activities. The measurement is 24 cm long, which covers much of the front and back of the delicate area of the underwear The proposal is divided into two parts, which consists of the validation and development of the business plan. For the execution of this project, an investment of 23,888 soles was required, it is obtained solely on the shareholder's own capital, with an estimated payback in the first year of operations. The profitability provided to the shareholders is 274%, which makes the project a profitable business. / Trabajo de investigación

The studies in this thesis are mainly focused on the effects that the chaperonin mechanisms have on a bound target protein. Earlier studies have shown that the bacterial chaperonin GroEL plays an active role in unfolding a target protein during the initial binding. Here, the effects of the eukaryotic chaperonin TRiC’s mechanical action on a bound target protein were studied by fluorescence resonance energy transfer (FRET) measurements by attaching the fluorophore fluorescein to specific positions in the structure of the target protein, β-actin. Actin is an abundant eukaryotic protein and is dependent on TRiC to reach its native state. It was found that at the initial binding to TRiC, the actin structure is stretched, particularly across the nucleotide-binding site. This finding led to the conclusion that the binding-induced unfolding mechanism is conserved through evolution. Further studies indicated that in a subsequent step of the chaperonin cycle, the actin molecule collapses. This collapse leads to rearrangements of the structure at the nucleotide-binding cleft, which is also narrowed as a consequence. As a comparison to the productive folding of actin in the TRiC chaperonin system, FRET studies were also performed on actin interacting with GroEL. This is a non-productive interaction in terms of guiding actin to its native state. The study presents data indicating that the nucleotide-binding cleft in actin is not rearranged by GroEL in the same way as it is rearranged during the TRiC interaction. Thus, it could be concluded that although the general unfolding mechanism is conserved through the evolution of the chaperonins, an additional and specific binding to distinct parts of the actin molecule has evolved in TRiC. This specific binding leads to a directed unfolding and rearrangement of the nucleotide-binding cleft, which is vital for actin to reach its native state. The differences in the chemical properties of the actin-GroEL and the actin-TRiC complexes were also determined by measurements of fluorescein anisotropies and AEDANS emission shifts for probes attached to positions spread throughout the actin structure. The evolutionary aspects of the chaperonin mechanisms and the target protein binding were further investigated in another study. In this study, the prokaryotic homologue to actin, MreB, was shown to bind to both TRiC and GroEL. MreB was also shown to bind to the co-chaperonin GroES. In a separate study, the interaction between actin and the chaperone prefoldin was investigated. In vivo prefoldin interacts with non-native actin and transfers it to TRiC for subsequent and proper folding. In this homo-FRET study, it was shown that actin binds to prefoldin in a stretched conformation, similar to the initial binding of actin to TRiC. / On the day of the defence date the satus of article I was: In press.

Thesis (D. Min.)--Ashland Theological Seminary, 2008. / Abstract . Includes project proposal. Description based on microfiche version record. Includes bibliographical references (leaves 158-159, 181-189).

Thesis (D. Min.)--Ashland Theological Seminary, 2008. / Abstract . Includes project proposal. Includes bibliographical references (leaves 158-159, 181-189).

Alternative energy research into hydrogen production via water electrolysis addresses environmental and sustainability concerns associated with fossil fuel use. Renewable-powered electrolyzers are foreseen to produce hydrogen if energy and cost requirements are achieved. Electrocatalysts reduce the energy requirements of operating electrolyzers by lowering the reaction kinetics at the electrodes. Platinum group metals (PGMs) tend to be utilized as electrocatalysts but are not readily available and are expensive. Ni1-xMox alloys, as low-cost and earth-abundant transition metal nanoparticles (NPs), are emerging as promising electrocatalyst candidates to replace expensive PGM catalysts in alkaline media. Pure-phase cubic and hexagonal Ni1-xMox alloy NPs with increasing Mo content (0–11.4%) were synthesized as electrocatalysts for the hydrogen evolution reaction (HER). In general, an increase in HER activity was observed with increasing Mo content. The cubic alloys were found to exhibit significantly higher HER activity in comparison to the hexagonal alloys, attributed to the higher Mo content in the cubic alloys. However, the compositions with similar Mo content still favored the cubic phase for higher activity. To produce a current density of -10 mA/cm2, the cubic and hexagonal alloy NPs require over-potentials ranging from -62 to -177 mV and -162 to -242 mV, respectively. The cubic alloys exhibited over-potentials that rival commercial Pt-based electrocatalysts (-68 to -129 mV at -10 mA/cm2). The cubic Ni0.934Mo0.066 alloy NPs showed the highest alkaline HER activity of the electrocatalysts studied and therefore a patent application was submitted. Bulk Ni–Mo phases have been known as electrocatalysts for the HER for decades, while recently transition metal phosphides (TMPs) have emerged as stable and efficient PGM alternatives. Specifically, Ni2P has demonstrated good HER activity and improved stability for both alkaline and acidic media. However, Ni2P electrocatalysts are a compromise between earth-abundance, performance (lower than Ni–Mo and PGMs) and stability. For the first time Ni–Mo–P electrocatalysts were synthesized with varying atomic ratios of Mo as electrocatalysts for alkaline HER. Specific phases, compositions and morphologies were studied to understand the intrinsic properties of TMPs leading to high HER activity. The Ni1.87Mo0.13P and Ni10.83Mo1.17P5 NPs were shown to be stable for 10 h at –10 mA cm-2 with over-potentials of –96 and –82 mV in alkaline media, respectively. The Ni1.87Mo0.13P and Ni10.83Mo1.17P5 NPs exhibited an improved performance over the synthesized Ni2P sample (–126 mV at –10 mA cm-2), likely a result of the overall phosphorous content and hetero-structured morphologies. A strong correlation between phase dependence and the influence of Mo on HER activity needs to be further investigated. Furthermore, understanding the intrinsic properties of electrocatalysts leading to high water splitting performance and stability can apply electrocatalysts in other research applications, such as photoelectrochemical (PEC) water splitting, water remediation and sustainable chemical processing applications. Contributions to photocatalytic water remediation and electrochemical chlorinated generation to halogenate pyridone-based molecules are reported. Electrochemical techniques were developed and reported herein to aid in understanding electrochemical performance, chemical mechanisms and the stability of electrocatalysts at the electrode-electrolyte interfaces.

O desenvolvimento de células de combustível de formato direto encontra obstáculos importantes relacionados com a lenta cinética da reação de redução de oxigênio e baixa tolerância ao formato em cátodos baseados em Pt. Neste estudo, foram sintetizados eletrocatalisadores com diferentes estruturas, formados por elementos abundantes, e suas atividades e seletividades para a RRO foram testadas em meiacélulas e em células unitárias de formato / ar, em eletrólito alcalino. Os resultados mostraram que nanopartículas de liga de ferro-cobalto, encapsuladas por carbono grafítico, e nitretos metálicos nanoestruturados, suportados em carbono, (caracterizados por TEM e XRD) não apresentam atividades eletrocatalíticas superiores ao carbono puro (Vulcan amorfo ou grafitizado). Carbono dopado com nitrogênio (N-C) mostrou um aumento no potencial de meia-onda, evidenciando um influente papel do nitrogênio na eletrocatálise da RRO, mas com alto sobrepotencial. A inserção de oxigênio via tratamento térmico em ar, formando óxidos de FeCo nanoestruturados, suportados por carbono, produziu, como esperado, um aumento considerável na atividade, mostrando que a ligação do ferro ou cobalto com o oxigênio tem papel importante, provavelmente, na alta reatividade redox para a transferência de elétrons para o RRO. A adição de um precursor de nitrogênio durante a síntese (imidazol) resultou na formação de estruturas formadas por átomos de ferro e cobalto, coordenados por nitrogênio, inseridos em uma matriz de carbono, como revelado por EXAFS, mostrou que as estruturas M-N-C têm papel decisivo na atividade eletrocatalítica para a RRO (aproximando-se da Pt/C) e, também, mostrou alta tolerância à presença de íons formato. Experimentos em células a combustível unitárias, com difusão natural de formato e com cátodo aberto ao ar, com elétrodo de difusão de gás, mostraram densidades de potência de 15,5 e 10,5 mW cm-2 com eletrólitos à base de hidróxido e carbonato de potássio, respectivamente, e com estabilidade de operação maior que 120 h a 0,3 mA cm-2. Portanto, os resultados deste trabalho mostram o papel decisivo de estruturas M-NC (coordenadas) na alta atividade para a ORR, em altos potenciais, excluindo-se atividades atribuídas a nanoestruturas de nitretos metálicos e nanopartículas metálicas encapsuladas, incluindo as dopadas por nitrogênio na superfície. / The development of direct formate fuel cells encounters significant obstacles related to the slow kinetics of the oxygen reduction reaction (ORR) and low formate tolerance in Pt-based cathodes. In this study, electrocatalysts with different structures, composed of abundant elements, were synthesized, and their activities and selectivities for the ORR were tested in half-cells and in single cells in alkaline electrolyte. The results showed that carbon-encapsulated nanoparticles of iron-cobalt alloy and carbon-supported nanostructured metal nitrides (characterized by TEM and XRD) do not present electrocatalytic activities superior to pure carbon (amorphous or graphitized Vulcan). Nitrogen-doped carbon (N-C) showed an increase in the halfwave potential, evidencing an influential role of nitrogen in the electrocatalysis of the ORR, but with a high overpotential. The insertion of oxygen through heat treatment in air, forming carbon-supported nanostructured FeCo oxides, produced, as expected, an increase in activity, probably due to the high oxide reactivity for the electronic mediation processes for the ORR. The addition of a nitrogen precursor during the synthesis (imidazole) resulted in the formation of structures formed by iron and cobalt atoms, coordinated by nitrogen, inserted in a carbon matrix, as revealed by EXAFS, and showed that M-N-C structures play a decisive role in the electrocatalytic activity for the ORR (approaching Pt/C) and, also, showed high tolerance to the presence of ions format. Experiments in single cells with air-breathing cathode and with natural diffusion of formate, showed power densities of 15.5 and 10.5 mW cm-2 with hydroxide and carbonate-based electrolytes, respectively, and with operating stability higher than 120 h at 0.3 mA cm-2. Therefore, the results of this work show the decisive role of M-N-C structures (coordination) in the high activity for the ORR, in high potentials, excluding activities attributed to nanostructures of metallic nitrides and encapsulated metallic nanoparticles, including those doped by surface nitrogen.

Energy conversion processes such as the water splitting and CO2 hydrogenation reactions have emerged as attractive approaches to mitigate environmental concerns on CO2 emissions as well as to provide an alternative source of renewable fuels. These strategic processes can capitalize on the energy of renewable resources (e.g solar and wind) to drive chemical reactions to generate, in a green and sustainable way, fuels and value-added chemicals. Economically feaseable heterogeneous catalysts play a central role in advancing such processes for globally-relevant production scales. Hence, in this work, we focused on the synthetic development of several catalyst systems based on cost-effective earth-abudant 3d transition metals such as nickel (Ni), cobalt (Co), iron (Fe) and zinc (Zn). Specifically, we turned our attention to produce a series of catalysts comprised of: i) NiFe oxyhydroxide supported on carbon for application in oxygen evolution reaction (OER), a bottleneck reaction for the water splitting process, and ii) Ni and Co nanoparticles supported on Zinc oxide (ZnO) for the CO2 hydrogenation reaction. Regarding the NiFe oxyhydroxide systems, we evaluated the catalytic performance of these materials towards the OER and benchmarked those with that of state-of-the-art OER electrocatalyts such as Ir/C. In addition to that, we also focused on rationalizing the key reasons for the significant enhancements in OER activity of such catalysts in terms of their surface and bulk compositions. For Co/ZnO and Ni/ZnO catalysts, aside from assessing their catalytic activity and selectivity behavior, we performed a systematic investigation of the catalytically important properties of such catalyst interfaces under typical CO2 hydrogenation reaction conditions using in situ ambient pressure X-ray photoelectron spectroscopy (AP-XPS). This allowed us to acquire important knowledge into the origin and the nature of the active sites associated with the catalytic activity and selectivity in these materials. / Processos de conversão de energia, como as reações de quebra de água e hidrogenação de CO2, têm surgirdo como abordagens atraentes para mitigar as preocupações ambientais das emissões de CO2, bem como para fornecer uma fonte alternativa de combustíveis renováveis. Esses processos estratégicos podem capitalizar a energia de recursos renováveis (por exemplo, solar e eólica) para realizar reações químicas que geram, de forma sustentável e ecológica, combustíveis e produtos químicos com valor agregado. Catalisadores heterogêneos economicamente viáveis desempenham um papel central no avanço de tais processos para escalas de produção globalmente relevantes. Assim, neste trabalho, nos concentramos no desenvolvimento sintético de vários sistemas catalisadores baseados em metais de transição 3d abudantes como o níquel (Ni), cobalto (Co), ferro (Fe) e zinco (Zn). Especificamente, voltamos nossa atenção para produzir uma série de catalisadores compostos de: i) oxi-hidróxido de NiFe suportado em carbono para aplicação na reação de evolução de oxigênio (OER), uma reação limitante para o processo de quebra de água, e ii) nanopartículas de Ni e Co suportadas em Óxido de zinco (ZnO) para a reação de hidrogenação do CO2. Com relação aos sistemas de oxi-hidróxido de NiFe, avaliamos o desempenho catalítico desses materiais frente a OER e comparamos estes com eletrocatalisadores para OER de última geração, como Ir/C. Além disso, também nos concentramos em racionalizar as principais razões para as melhorias significativas na atividade catalítica de tais catalisadores em termos de suas composições de superfície e volume. Para os catalisadores de Co/ZnO e Ni/ZnO, além de avaliar sua atividade catalítica e seletividade, realizamos uma investigação sistemática in situ das propriedades cataliticamente importantes de tais interfaces usando a Espectroscopia de Fotoelétrons de Raios X a Pressão Ambiente. (APXPS) sob condições típicas de reação de hidrogenação de CO2. Isso nos permitiu adquirir conhecimentos importantes sobre a origem e a natureza dos sítios ativos associados à atividade e seletividade catalítica nesses materiais.

O desenvolvimento de células de combustível de formato direto encontra obstáculos importantes relacionados com a lenta cinética da reação de redução de oxigênio e baixa tolerância ao formato em cátodos baseados em Pt. Neste estudo, foram sintetizados eletrocatalisadores com diferentes estruturas, formados por elementos abundantes, e suas atividades e seletividades para a RRO foram testadas em meiacélulas e em células unitárias de formato / ar, em eletrólito alcalino. Os resultados mostraram que nanopartículas de liga de ferro-cobalto, encapsuladas por carbono grafítico, e nitretos metálicos nanoestruturados, suportados em carbono, (caracterizados por TEM e XRD) não apresentam atividades eletrocatalíticas superiores ao carbono puro (Vulcan amorfo ou grafitizado). Carbono dopado com nitrogênio (N-C) mostrou um aumento no potencial de meia-onda, evidenciando um influente papel do nitrogênio na eletrocatálise da RRO, mas com alto sobrepotencial. A inserção de oxigênio via tratamento térmico em ar, formando óxidos de FeCo nanoestruturados, suportados por carbono, produziu, como esperado, um aumento considerável na atividade, mostrando que a ligação do ferro ou cobalto com o oxigênio tem papel importante, provavelmente, na alta reatividade redox para a transferência de elétrons para o RRO. A adição de um precursor de nitrogênio durante a síntese (imidazol) resultou na formação de estruturas formadas por átomos de ferro e cobalto, coordenados por nitrogênio, inseridos em uma matriz de carbono, como revelado por EXAFS, mostrou que as estruturas M-N-C têm papel decisivo na atividade eletrocatalítica para a RRO (aproximando-se da Pt/C) e, também, mostrou alta tolerância à presença de íons formato. Experimentos em células a combustível unitárias, com difusão natural de formato e com cátodo aberto ao ar, com elétrodo de difusão de gás, mostraram densidades de potência de 15,5 e 10,5 mW cm-2 com eletrólitos à base de hidróxido e carbonato de potássio, respectivamente, e com estabilidade de operação maior que 120 h a 0,3 mA cm-2. Portanto, os resultados deste trabalho mostram o papel decisivo de estruturas M-NC (coordenadas) na alta atividade para a ORR, em altos potenciais, excluindo-se atividades atribuídas a nanoestruturas de nitretos metálicos e nanopartículas metálicas encapsuladas, incluindo as dopadas por nitrogênio na superfície. / The development of direct formate fuel cells encounters significant obstacles related to the slow kinetics of the oxygen reduction reaction (ORR) and low formate tolerance in Pt-based cathodes. In this study, electrocatalysts with different structures, composed of abundant elements, were synthesized, and their activities and selectivities for the ORR were tested in half-cells and in single cells in alkaline electrolyte. The results showed that carbon-encapsulated nanoparticles of iron-cobalt alloy and carbon-supported nanostructured metal nitrides (characterized by TEM and XRD) do not present electrocatalytic activities superior to pure carbon (amorphous or graphitized Vulcan). Nitrogen-doped carbon (N-C) showed an increase in the halfwave potential, evidencing an influential role of nitrogen in the electrocatalysis of the ORR, but with a high overpotential. The insertion of oxygen through heat treatment in air, forming carbon-supported nanostructured FeCo oxides, produced, as expected, an increase in activity, probably due to the high oxide reactivity for the electronic mediation processes for the ORR. The addition of a nitrogen precursor during the synthesis (imidazole) resulted in the formation of structures formed by iron and cobalt atoms, coordinated by nitrogen, inserted in a carbon matrix, as revealed by EXAFS, and showed that M-N-C structures play a decisive role in the electrocatalytic activity for the ORR (approaching Pt/C) and, also, showed high tolerance to the presence of ions format. Experiments in single cells with air-breathing cathode and with natural diffusion of formate, showed power densities of 15.5 and 10.5 mW cm-2 with hydroxide and carbonate-based electrolytes, respectively, and with operating stability higher than 120 h at 0.3 mA cm-2. Therefore, the results of this work show the decisive role of M-N-C structures (coordination) in the high activity for the ORR, in high potentials, excluding activities attributed to nanostructures of metallic nitrides and encapsulated metallic nanoparticles, including those doped by surface nitrogen.

No description available.